EXAMPLES WEB TECH

HTML

HTML (Hyper Text Mark-up Language) is the glue that holds together every web site. HTML is an open source language (i.e. not owned by anyone), which is easy to learn and requires no fancy packages to start using it. All you need is something to type with, such as Windows Notepad, and a lot of time and patience.

HTML works on a 'tag' system, where each tag effects the content placed within that tag, e.g.

<TAG>What the tag effects</TAG>.

Although relatively limited by itself, it is the flexibility of HTML that allows web sites to grow in complexity. Like the foundation of your house, HTML is robust enough to support many kinds of languages integrated within your HTML pages.

CSS

CSS (Cascading Style Sheets) is a relatively new language, designed to expand upon the limited style properties of HTML. Easy to learn and implement, CSS is an excellent way to control the style of your site, such as text styles like size, colour and font.

CSS may also be placed inside the HTML page or in separate files. The real advantage of having all of the style properties for your entire site in one single CSS file is that you may edit that single file to effect changes on the whole site, rather than having to go through each HTML file one at a time. For this reason, it is perhaps the most useful web technology.

JAVASCRIPT

JavaScript is a 'scripting' language. A bit like a script in a feature film, it is used to decide 'what happens next'. This may be a sequence of screen events, where one event is initiated by the end of another, or it could be a programmed response to a user interacting with the page in some way, e.g. moving their mouse over a link. JavaScript is a complex and powerful language, and may be placed directly inside a HTML page, or in a separate JavaScript file.

DOM

DOM (Document Object Model) allows the designer to access any element in a HTML page, such as an image, layer or table. Each element may be assigned a unique 'id' name to identify it by, e.g.

<TAG ID="My Tag">Content of My Tag</TAG>

When combined with CSS and JavaScript, the DOM may be used to make changes to only "My Tag" and no other element, such as increasing text size or the position of "My Tag" on the screen. JavaScript my also be used to animated such changes to any identified element, such as gradually increasing the size of the text on screen.

Each different browser has it's own DOM, and this is often used to determine which browser the visitor is using. A particular action may be carried out if the person is using NS6, for example, and ignored if the person is using IE5.